Structural mimicking of inorganic catalyst supports with polydivinylbenzene to improve performance in the selective aerobic oxidation of ethanol and glycerol in water

Abstract

Many forms of polymers have been prepared and studied as polymeric catalyst support for metal nanoparticles and solid acid catalysts. The nanocasted mesoporous polydivinylbenzene (PDVB)-supported platinum catalysts presented here are distinguished by their customized mesoporosity and bulk morphology that are comparable to typical carbon- and alumina-supported powdered catalysts. Platinum nanoparticles are deposited on PDVB at loadings between 1wt% and 9wt% and a mean size between 2.7nm and 6.2nm, dependent on the synthesis method. Bifunctional catalysts containing platinum and acidic functionality are prepared by gas-phase sulfonation of the Pt/PDVB catalysts. The PDVB-supported catalysts are active for the oxidation of ethanol with molecular oxygen in water with up to 94% yield of acetic acid. In the analogous oxidation of glycerol, up to 60% yield of glyceric acid is reached with the bifunctional catalyst, and the polymer-supported catalysts feature lower formation of unidentified side products than Pt/C and Pt/Al2O3. Altogether, we find the polymers to be more active than the alumina and more selective than the carbon supports and thus overall have optimized performance.